JP6168906B2 - Lens barrel - Google Patents

Description

  The present invention relates to a lens barrel capable of driving a lens group such as a focus lens and a zoom lens by an autofocus mechanism and a manual operation of an operation ring.

  As a photographing method using an imaging device such as a digital camera or a video camera, there is a method of focusing using a distance scale at each focal length at the time of photographing. When performing such shooting, it is necessary to improve the focus feed accuracy, and it is also necessary to improve the operation accuracy when setting an arbitrary focal length in the zoom operation.

  Therefore, an inner barrel whose surface is coated with a viscous fluid, an operation ring that rotates relative to the inner barrel, a contact member that is fixed to the operation ring so as to contact the inner barrel, an operation ring, A lens barrel having an adjustment member that changes the contact amount of the contact member by changing the positional relationship is proposed (see Patent Document 1).

Japanese Patent Laid-Open No. 8-28602

  However, in the technique described in Patent Document 1, when adjusting the weight for operating the operation ring, an operation of rotating the adjustment member relative to the operation ring is necessary. There is a problem that the shooting must be interrupted in order to perform.

  It is an object of the present invention to provide a lens barrel that can change the rotational load of the operating ring during the rotating operation of the operating ring.

A lens barrel according to the present invention is a lens barrel that moves a lens in an optical axis direction by rotation of an operation ring that is arranged to be rotatable about an optical axis relative to a fixed ring, ring e given a rotational load to the rotation of the operating ring when rotation operation, have the brake vary with the magnitude of the rotation load is the operation ring in the optical axis direction of the lens barrel is operated The braking portion includes an operation ring protrusion provided on the operation ring, an urging spring for urging the operation ring protrusion on the fixed ring, and a friction ring provided on the fixed ring. And a rotational load is generated by frictional sliding between the friction ring and the operation ring protrusion, and the operation ring protrusion is separated from the friction ring against an urging force of the urging spring. The ring is in the optical axis direction relative to the stationary ring. If the bulk is characterized in that the rotational load is reduced resulting in the braking portion.

  In the present invention, the magnitude of the rotational load generated by the braking unit that applies a rotational load to the rotation of the operation ring is changed when the operation ring is operated in a direction different from the rotation direction of the operation ring. As a result, when the operating ring is rotated manually, the rotation load of the operating ring can be freely changed, so there is no need to interrupt shooting and the operability of the operating ring during shooting can be improved. .

1 is a partial side sectional view of a lens barrel according to a first embodiment of the present invention. It is arrow AA sectional drawing in FIG. 1, and arrow B direction top view. FIG. 2 is a side cross-sectional view schematically showing a method for switching a rotation load of an operation ring provided in the lens barrel of FIG. 1. FIG. 2 is a side sectional view showing a schematic structure of an interchangeable lens barrel in which an operation ring of the lens barrel of FIG. 1 is applied to a zoom ring and a focus ring. It is a partial side sectional view of a lens barrel according to a second embodiment of the present invention. FIG. 6 is a side cross-sectional view schematically showing a method for switching a rotation load of an operation ring provided in the lens barrel of FIG. 5. FIG. 7 is a cross-sectional view taken along the line CC in FIG. 6 and a plan view taken in the direction of the arrow D. FIG. 6 is a side sectional view showing a schematic structure of an interchangeable lens barrel in which an operation ring of the lens barrel of FIG. 5 is applied to a zoom ring and a focus ring.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

<First Embodiment>
FIG. 1 is a partial side sectional view of a lens barrel 1 according to a first embodiment of the present invention. The lens barrel 1 includes a fixed ring 5 and an operation ring 8. The operation ring 8 is rotatable relative to the fixed ring 5 around the optical axis, and the zoom operation or the focus operation can be performed by this rotation. Further, the operation ring 8 can move (slide) in the optical axis direction, and in a normal state, the operation ring 8 is pressed against the subject side by a biasing force F by a biasing spring 9 attached to the fixed ring 5.

  A part of the operation ring 8 and the operation ring projection 8a inside the lens barrel 1 are arranged in parallel with the optical axis. The operation ring protrusion 8 a is disposed in a space 5 a formed between a part of the fixed ring 5 and a substantially L-shaped cross section provided inside the lens barrel 1 and the main body of the fixed ring 5. It is pressed against the friction ring 7. A space 5a of the stationary ring 5 in which the friction ring 7 is disposed is filled with a viscous fluid 6. Since the viscous fluid 6 needs to be held in the space 5a of the stationary ring 5, for example, a paste-like high-viscosity fluid (for example, silicon grease) is preferably used. In the present embodiment, the friction ring 7, the viscous fluid 6, and the biasing spring 9 constitute a braking portion.

  In order to prevent frictional resistance between the biasing spring 9 and the fixed ring 5 due to the biasing force of the biasing spring 9 when the operation ring 8 is rotated, the biasing spring 9 and the fixed ring 5 are prevented. A washer 10 is disposed between the two.

  2A is a cross-sectional view taken along the line AA in FIG. 1 (cross-sectional view orthogonal to the optical axis direction), and FIG. 2B is a plan view taken along the direction B in FIG. Figure). In FIG. 2A, the friction ring 7 and the viscous fluid 6 should not appear, but the operation ring protrusion 8a is shown to be pressed by indicating them with a broken line.

  The operating ring projection 8a is pressed against the friction ring 7 by the urging force F of the urging spring 9, and a drag force is generated. A resistance force K due to friction is generated in the direction opposite to the rotation direction with respect to the rotation of the operating ring 8. In this state, when the operation ring 8 is rotated about the optical axis with respect to the fixed ring 5 in order to perform the zoom operation or the focus operation, the sliding resistance caused by the frictional sliding between the operation ring projection 8a and the friction ring 7 is achieved. Occurs. The viscous fluid 6 is caught by frictional sliding between the operating ring projection 8a and the friction ring 7, prevents the feeling of being pulled around, and is prevented from coming off, and generates a viscous resistance. This viscous resistance increases the rotational load of the operating ring 8. By doing so, the operation ring 8 can be finely rotated.

  Next, a method for switching the rotational load of the operation ring 8 (a method for reducing the rotational load) will be described with reference to FIG. FIG. 3 is a side sectional view schematically showing a method for switching the rotational load of the operation ring 8. When the operation ring 8 is rotated about the optical axis for the zoom operation or the focus operation, a force J greater than the urging force F of the urging spring 9 is generated in the operation ring 8 so that the operation ring 8 is fixed to the fixed ring 5. On the other hand, it is moved to the image plane (imaging plane) side. That is, by operating the operation ring 8 in a direction different from the rotation operation so that the operation ring protrusion 8a which is a part of the operation ring 8 is separated from the friction ring 7, the operation ring protrusion 8a and the friction ring 7 The sliding load of the operation ring 8 is reduced by reducing or eliminating the sliding resistance.

  As described above, when fine adjustment of the operation ring 8 is performed, the operation ring 8 in the normal state is rotated with respect to the fixed ring 5 around the optical axis. At this time, the rotational load of the operating ring 8 needs to be rotated against the load caused by the sliding resistance between the operating ring projection 8a and the friction ring 7 and the high viscosity of the viscous fluid 6, so the rotational load Is big. As described above, when the rotation load of the operation ring 8 is large, the operation time takes a long time, but fine rotation (rotation of a small angle) is possible, which is suitable for fine adjustment of the focus operation.

  On the other hand, when the coarse adjustment of the operation ring 8 is performed, a force J is generated in the operation ring 8 to move the operation ring 8 toward the image plane side in the optical axis direction with respect to the fixed ring 5, and the operation ring protrusion The part 8a is separated from the friction ring 7 and rotated around the optical axis. At this time, since the rotation load of the operation ring 8 is small, the operation ring 8 can be rotated quickly, and is thus suitable for coarse adjustment of the focus operation.

  In the lens barrel 1 according to the present embodiment, since the operation direction of the operation ring 8 for driving the lens is different from the operation direction of the operation ring for adjusting the rotational load, the operation ring 8 is moved in the optical axis direction. The operation can be performed during the rotation operation of the operation ring 8 and vice versa. That is, during the rotation operation of the operation ring 8 for performing the fine movement operation of the operation ring 8, the operation ring 8 can be switched to the moving operation for performing the coarse movement operation, and vice versa. Can also be done.

  Next, an interchangeable lens barrel 21 in which an operation ring 8 that can arbitrarily perform a rotation operation and a movement operation, which is a characteristic configuration of the lens barrel 1 described above, is applied to a zoom ring and a focus ring is illustrated in FIG. This will be described with reference to FIG. FIG. 4 is a side sectional view showing a schematic structure of the interchangeable lens barrel 21. In the interchangeable lens barrel 21, the operations described with reference to FIGS. 1 to 3 are applied to the structure of the zoom ring 41 and the focus ring 42 that drive the lens holding frame (lens holding member) that holds the zoom lens and the focus lens, respectively. The structure of ring 8 is applied.

  In the interchangeable lens barrel 21, from the subject side to the image plane side, the first group zoom lens 22 held by the first group lens holding frame 25, the second group zoom lens 23, 3 held by the second group lens holding frame 26, and 3 The focus lens 24 held by the group lens holding frame 27 is arranged in this order. The first group zoom lens 22 and the second group zoom lens 23 are optical axis direction moving lenses having a zooming action. The focus lens 24 is an optical axis direction moving lens that performs focus adjustment and image plane correction.

  On the outer peripheral portion of the first group lens holding frame 25, three cam pins 25a are projected at equal intervals in the circumferential direction. Each cam pin 25 a is inserted into three straight advance grooves 28 a formed in the inner fixed ring 28, and simultaneously engaged with three cam grooves 29 a formed in the cam ring 29. By rotation of the cam ring 29, each cam pin 25a moves along the trajectory of each inserted cam groove 29a, whereby the first group zoom lens 22 can be moved in the optical axis direction. Each cam pin 25a also serves as a rectilinear guide for moving the first group zoom lens 22 in the optical axis direction. By arranging the three cam pins 25a on the first group lens holding frame 25 at equal intervals (equal). , The straight movement accuracy is improved.

  Similar to the first group lens holding frame 25, cam pins 26 a protrude from the outer peripheral portion of the second group lens holding frame 26 at three equal intervals in the circumferential direction. Each cam pin 26 a is inserted into three straight advance grooves 28 b formed in the inner fixed ring 28 and simultaneously engaged with three cam grooves 29 b formed in the cam ring 29. By rotation of the cam ring 29, each cam pin 26a moves along the locus of each inserted cam groove 29b, whereby the second group zoom lens 23 can be moved in the optical axis direction. Each cam pin 26a also serves as a rectilinear guide for moving the second group zoom lens 23 in the optical axis direction. By arranging three cam pins 26a at equal intervals on the second group lens holding frame 26, each cam pin 26a moves straight. The accuracy is increased.

  A stepping motor 32 is used as a drive source for moving the third group lens holding frame 27 that holds the focus lens 24 in the optical axis direction. A nut 34 is attached to the third group lens holding frame 27, and the nut 34 is screwed to the lead screw 33. Therefore, when the stepping motor 32 rotates the lead screw 33, the third group lens holding frame 27 is moved in the optical axis direction by moving in the optical axis direction of the nut 34. At this time, the guide bar 35 plays a role as a guide for moving the third group lens holding frame 27 in the optical axis direction. The play in the optical axis direction of the third group lens holding frame 27 is corrected by a biasing spring (not shown).

  On the image plane side of the interchangeable lens barrel 21, a mount 36 that can be coupled to a mount of a camera body (not shown) is provided. A diaphragm shutter unit 37 is attached to the second group lens holding frame 26 so as to be disposed between the first group zoom lens 22 and the second group zoom lens 23. Shutter operation is performed. The diaphragm shutter unit 37 moves in the optical axis direction integrally with the second group lens holding frame 26 as the second group lens holding frame 26 moves in the optical axis direction.

  The interchangeable lens barrel 21 has an outer fixed ring 5A. A zoom ring 41 and a focus ring 42 having a rotation load adjusting mechanism are attached to the outer fixed ring 5A. The outer fixed ring 5A corresponds to the fixed ring 5 described with reference to FIGS. 1 to 3, and the zoom ring 41 and the focus ring 42 correspond to the operation ring 8 described with reference to FIGS. 1 to 3, respectively.

  The zoom ring 41 has a moving part 41a movable in the optical axis direction and a fixed part 41b fixed to the outer fixed ring 5A. The fixed part 41b is mechanically coupled (mechanically coupled) to the cam ring 29. Has been. The backlash correction in the optical axis direction of the cam ring 29 is performed by a biasing spring (not shown). The focus ring 42 is an electronic ring and does not have a stroke end in the rotation direction, and has a structure that can be rotated indefinitely. Both the zoom ring 41 and the focus ring 42 are pressed against the subject side by the urging force F of the urging spring 9 attached to the outer fixed ring 5A.

  The interchangeable lens barrel 21 is provided with a zoom ring position detection sensor 63 and a focus ring position detection sensor 64 for each of the zoom ring 41 and the focus ring 42. The focus ring position detection sensor 64 detects the rotation amount of the focus ring 42 around the optical axis, and the zoom ring position detection sensor 63 detects the rotation amount of the zoom ring 41 around the optical axis. Based on the output signals of the zoom ring position detection sensor 63 and the focus ring position detection sensor 64, the lens microcomputer 65 provided in the interchangeable lens barrel 21 determines the amount of movement of the focus lens 24 in the optical axis direction and drives the stepping motor 32. Let This allows manual focus operation.

  When the zoom ring 41 is manually rotated about the optical axis with respect to the outer fixed ring 5A in order to perform the zoom operation, in the state shown in FIG. 4, the zoom ring protrusion 41c contacts the friction ring 7 and the viscous fluid 6. As a result, the rotational load is increased, so that a fine motion rotation operation is possible. This means that the cam ring 29 can be finely rotated, and that the cam ring 29 can be finely moved in the optical axis direction. Even when the focus ring 42 is rotated about the optical axis with respect to the outer fixed ring 5A in order to perform the focusing operation, it can be rotated finely by the same configuration. Therefore, the fine movement of the focus lens 24 in the optical axis direction can be performed. It can be carried out.

  Similar to the description with reference to FIG. 3, the zoom ring 41 is moved to the image plane side in the optical axis direction with respect to the outer fixed ring 5A by a force J (not shown in FIG. 4) greater than the biasing force F by the biasing spring 9. By rotating the lens around the optical axis, the zoom ring projection 41c moves away from the friction ring 7 and the sliding resistance is reduced. In this way, the rotation load of the zoom ring 41 is reduced, so that the coarse rotation operation can be performed. The fact that the zoom ring 41 can be coarsely rotated means that the cam ring 29 can be coarsely rotated, which means that the cam ring 29 can be coarsely moved in the optical axis direction. When the focus ring 42 is rotated about the optical axis with respect to the outer fixed ring 5A in order to perform the focusing operation, coarse movement rotation is possible with the same configuration, and therefore, the coarse rotation of the focus lens 24 in the optical axis direction is possible. Can be moved.

  As described above, in the interchangeable lens barrel 21, the rotation load of the zoom ring 41 and the focus ring 42 for moving the first group zoom lens 22, the second group zoom lens 23, and the focus lens 24 in the optical axis direction is rotated. You can switch in. As a result, the fine and coarse movements of each lens can be performed arbitrarily, and the zoom operability and focus operability during shooting are improved.

Second Embodiment
FIG. 5 is a partial cross-sectional side view of a lens barrel 1A according to the second embodiment of the present invention. The lens barrel 1 </ b> A includes a fixed ring 50 and an operation ring 51. The operation ring 51 can be rotated relative to the fixed ring 50 about the optical axis, and the zoom operation or the focus operation can be performed by this rotation.

  The operation ring 51 includes a soft material portion 51a having an outer side made of a soft material such as rubber or a flexible resin, and a hard material portion 51b having an inner side made of a hard material such as a hard resin. The soft material portion 51a is provided with a ring-shaped protrusion 51c that protrudes inward, and an annular spring 52 is disposed at the root of the ring-shaped protrusion 51c. The annular spring 52 urges the operating ring 51 toward the outer diameter side (outer in the radial direction) with respect to the optical axis, whereby the shape of the soft material portion 51a is maintained.

  In the state of FIG. 5, the tip of the ring-shaped protrusion 51 c provided on the soft material portion 51 a is connected to the friction ring 54 disposed in the space 50 a of the recess (annular groove) provided on the outer periphery of the stationary ring 50. Although facing each other, the friction ring 54 is not in contact with each other and is in a separated state. In addition, the space 50a between the tip of the ring-shaped protrusion 51c and the friction ring 54 is filled with the viscous fluid 53 and held. In addition, the characteristic calculated | required by the viscous fluid 53 is based on the viscous fluid 6 demonstrated in 1st Embodiment, and abbreviate | omits description here. In the second embodiment, the friction ring 54 and the viscous fluid 53 constitute a braking portion.

  Therefore, when the operation ring 51 is rotated about the optical axis with respect to the fixed ring 50 in the state of FIG. 5, the ring-shaped protrusion 51c is not in contact with the friction ring 54, so there is no large sliding resistance. The operation ring 51 can be rotated with a small rotational load. That is, in the state of FIG. 5, the coarse rotation operation of the operation ring 51 can be performed.

  Next, with reference to FIG. 6, a method for switching the rotational load of the operation ring 51 (a method for increasing the rotational load) will be described. FIG. 6 is a side cross-sectional view schematically showing a method for switching the rotational load of the operation ring 51. Moreover, Fig.7 (a) is arrow CC sectional drawing in FIG. 6, FIG.7 (b) is an arrow D direction top view in FIG.

  When performing the zoom operation or the focus operation, if the operator wishes to finely rotate the operation ring 51 around the optical axis by manual operation, the operator grasps the outer peripheral surface of the ring-shaped protrusion 51c of the operation ring 51 and moves the inner ring side ( A pressing force P toward the radially inner side is generated. That is, the operation ring 51 is operated in a direction different from the rotation operation of the operation ring 51. Then, with this pressing force P, the soft material portion 51 a and the annular spring 52 are deformed, the tip of the ring-shaped protrusion 51 c is brought into contact with the friction ring 54 and pressed against the friction ring 54.

  In other words, when it is desired to finely rotate the operation ring 51, the operation is performed so that a pressing force P is generated so that the tip of the ring-shaped protrusion 51 c comes into contact with at least the friction ring 54 and is further pressed against the friction ring 54. The person needs to hold the operation ring 51. That is, as long as the pressing force P generated by the operator grasping the operation ring 51 is such that the tip of the ring-shaped protrusion 51c cannot be brought into contact with the friction ring 54, the state shown in FIG. 5 is not changed. The rotational load remains small.

  As shown in FIG. 7A, when the ring-shaped protrusion 51c is pressed against the friction ring 54 by the pressing force P, a drag force having a magnitude corresponding to the pressing force P is generated. A resistance force S due to friction is generated in the direction opposite to the rotation direction with respect to the rotation. In FIG. 7B, the resistance force S is generated in a direction perpendicular to the paper surface. In this state, when the operation ring 51 is rotated with respect to the fixed ring 50 about the optical axis in order to perform the zoom operation or the focus operation, the sliding resistance due to the frictional sliding between the ring-shaped protrusion 51 c and the friction ring 54 is achieved. Occurs. The viscous fluid 53 is caught by frictional sliding between the ring-shaped protruding portion 51c and the friction ring 54, prevents a feeling of sensation, and slips off, and generates a viscous resistance. The viscous resistance increases the rotational load of the operation ring 51. By doing so, the operation ring 51 can be finely rotated.

  Thus, in the lens barrel 1A, the magnitude of the rotational load when the operating ring 51 is rotated can be adjusted by changing the magnitude of the force with which the operator grips the operating ring 51. Therefore, the operator can operate the operation ring 51 with an arbitrary force according to preference and intention, and the operability is improved.

  As described above, when the coarse rotation (coarse adjustment) of the operation ring 51 is performed, the operation ring 51 is rotated as it is (without grasping the operation ring 51 so as not to be deformed). Thereby, the rotation load of the operation ring 51 does not increase, and the operation ring 51 can be rotated with a small rotation load. On the other hand, when performing fine rotation (fine adjustment) of the operation ring 51, the ring-shaped protrusion 51 c of the operation ring 51 is pressed against the friction ring 54 while holding the operation ring 51 with a pressing force P that increases the rotational load. Rotate. Thereby, since the rotational load of the operation ring 51 becomes large, fine adjustment operation can be performed.

  Needless to say, generating the pressing force P by grasping the operation ring 51 can be arbitrarily performed during the rotation operation of the operation ring 51. That is, the disturbance rotation operation and the fine rotation operation of the operation ring 51 can be arbitrarily switched during the operation of rotating the operation ring 51.

  Next, an interchangeable lens barrel 21A in which the operation ring 51 which is a characteristic configuration of the lens barrel 1A described above is applied to a zoom ring and a focus ring will be described with reference to FIG. FIG. 8 is a side sectional view showing a schematic structure of the interchangeable lens barrel 21A. The structure of the operation ring 51 is applied to the structure of the zoom ring 61 and the focus ring 62 that drive the lens holding frame (lens holding member) that holds the zoom lens and the focus lens in the interchangeable lens barrel 21A. In the description of the interchangeable lens barrel 21A, portions equivalent to those of the interchangeable lens barrel 21 in FIG. 4 are denoted by the same reference numerals in FIG. 8 and description thereof is omitted, and only different components are described below. I will explain.

  A zoom ring 61 and a focus ring 62 are attached to the outer fixed ring 50A of the interchangeable lens barrel 21A. Both the zoom ring 61 and the focus ring 62 have the same configuration as the operation ring 51 shown in FIG. Then, similarly to the interchangeable lens barrel 21 of FIG. 4, the zoom ring 61 is mechanically coupled to the cam ring 29, and the zoom ring 61 is rotated about the optical axis to thereby rotate the first group zoom lens 22 and the second group zoom lens. 23 can be moved in the optical axis direction. Further, the focus lens 24 can be moved in the optical axis direction by rotating the focus ring 62.

  When the zoom ring 61 is rotated relative to the outer fixed ring 50A in order to perform a zoom operation in the interchangeable lens barrel 21A, there is no large sliding resistance as described with reference to FIG. The zoom ring 61 can be coarsely rotated by force. In the case where the focus ring 62 is rotated about the optical axis with respect to the outer fixed ring 50A in order to perform the focus operation, coarse movement rotation is possible with the same configuration.

  On the other hand, as described with reference to FIG. 6, the zoom ring 61 is gripped to generate a pressing force P, the annular spring 52 of the zoom ring 61 is deformed, and the ring-shaped protrusion of the zoom ring 61 is attached to the friction ring 54. In contact with As a result, the rotational load when rotating the zoom ring 61 is increased, so that fine rotation is possible, and as a result, the cam ring 29 can be finely moved in the optical axis direction. Even when the focus ring 62 is rotated about the optical axis with respect to the outer fixed ring 50A in order to perform the focusing operation, it can be finely rotated by the same configuration. As a result, the focus lens 24 is finely moved in the optical axis direction. Can be made.

  As described above, even in the interchangeable lens barrel 21A, the rotational loads of the zoom ring 61 and the focus ring 62 for moving the first group zoom lens 22, the second group zoom lens 23, and the focus lens 24 in the optical axis direction are rotated. You can switch in. As a result, the fine and coarse movements of each lens can be performed arbitrarily, and the zoom operability and focus operability during shooting are improved. Further, since the operator can change the rotational load when the zoom ring 61 and the focus ring 62 are finely rotated depending on the magnitude of the force gripping the zoom ring 61 and the focus ring 62, it is highly convenient for the operator. .

<Other embodiments>
Although the present invention has been described in detail based on preferred embodiments thereof, the present invention is not limited to these specific embodiments, and various forms within the scope of the present invention are also included in the present invention. included. Furthermore, each embodiment mentioned above shows only one embodiment of this invention, and it is also possible to combine each embodiment suitably.

DESCRIPTION OF SYMBOLS 1,1A Lens barrel 5,50 Fixed ring 6,53 Viscous fluid 7,54 Friction ring 8,51 Operation ring 8a Operation ring projection part 9 Energizing spring 10 Washer 21,21A Interchangeable lens barrel 41, 61 Zoom ring 42 , 62 Focus ring 51a Soft material part 51b Hard material part 52 Ring spring

Claims (6)

A lens barrel that moves the lens in the optical axis direction by rotation of an operation ring that is arranged to be rotatable about the optical axis relative to the fixed ring;
The example given a rotational load to the rotation of the operation ring, brake vary by the size of the rotary load the operating ring is operated in an optical axis direction of the lens barrel when the operating ring is operated to rotate Have
The braking portion includes an operation ring protrusion provided on the operation ring, an urging spring for urging the operation ring protrusion on the fixed ring, and a friction ring provided on the fixed ring. ,
A rotational load is generated by frictional sliding between the friction ring and the operation ring protrusion,
When the operation ring is moved relative to the fixed ring in the optical axis direction so that the operation ring protrusion is separated from the friction ring against the urging force of the urging spring, the braking unit The lens barrel is characterized in that the rotational load generated in the lens is reduced . An annular groove portion is provided on the inner peripheral surface of the stationary ring, with the optical axis as the center, the bottom surface being substantially orthogonal to the optical axis and the side surface being substantially parallel to the optical axis,
Wherein with said friction ring is disposed in the space of the groove, the lens barrel according to claim 1, viscous fluid in said space, characterized in that it is filled. A lens barrel that moves the lens in the optical axis direction by rotation of an operation ring that is arranged to be rotatable about the optical axis relative to the fixed ring;
There is a braking unit that applies a rotational load to the rotation of the operation ring when the operation ring is rotated, and the magnitude of the rotation load changes when the operation ring is operated in the radial direction of the lens barrel. And
The operating ring has a soft material portion on its outer periphery,
The braking portion includes a ring-shaped protrusion provided on the inner diameter side of the soft material portion, and an urging force that biases the soft material portion toward the outer diameter side so that the ring-shaped protrusion is separated from the stationary ring. A spring and a friction ring provided on the outer periphery of the stationary ring;
A rotational load occurs due to frictional sliding between the friction ring and the ring-shaped protrusion,
When the soft material portion such that the ring-shaped projections against the biasing force of the biasing spring is pressed against the friction ring Ru is pressed radially inward, that the rotational load of the operation ring increases features and, Relais lens barrel. On the outer peripheral surface of the stationary ring, a concave portion whose side surface is substantially orthogonal to the optical axis and whose bottom surface is substantially parallel to the optical axis is formed,
The lens barrel according to claim 3 , wherein the friction ring is disposed in the space of the concave portion, and the concave portion is filled with a viscous fluid. The lens barrel according to claim 3 or 4 , wherein the urging spring is an annular spring that urges the soft material portion toward an outer diameter side. The lens is a lens barrel according to any one of claims 1 to 5, characterized in that a focusing lens or a zoom lens.

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